. "A protein complex that forms a subcomplex of the 90S preribosome and can interact directly with the 5' External Transcribed Spacer (ETS) of the full length pre-rRNA transcript. In S. cerevisiae, it sediments at 25-30 S and is composed of Pwp2p, Dip2p, Utp21p, Utp13p, Utp18p, and Utp6p." . . . . "Pwp2p-containing subcomplex of 90S preribosome" . "25-30 S subcomplex of 90S preribosome" . "UTP-B complex" . . .